Lenalidomide G.L. (Lenalidomide)

Lenalidomide is an immunomodulatory agent used in hematologic malignancies and related disorders.

• Multiple Myeloma: improves progression‑free survival and disease control in relapsed or refractory patients.
• Myelodysplastic Syndromes with del(5q): reduces transfusion dependence and cytopenias.
• Mantle Cell Lymphoma: used in combination therapy for relapsed disease to achieve response.

• Lenalidomide binds to the cereblon component of the CRL4‑E3 ubiquitin ligase complex, altering substrate specificity. This interaction leads to ubiquitination and proteasomal degradation of transcription factors Ikaros (IKZF1) and Aiolos (IKZF3), resulting in modulation of cytokine production, inhibition of angiogenesis, and enhanced immune‑mediated tumor cell killing. It also affects the tumor microenvironment by reducing pro‑inflammatory signals and promoting natural killer cell activity.

Lenalidomide may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Fatigue: persistent tiredness affecting daily activities.
• Neutropenia: lowered neutrophil count increasing infection risk.
• Thrombocytopenia: reduced platelet count leading to easy bruising.
• Nausea: upset stomach and possible vomiting.
• Constipation: difficulty passing stools.
• Rash: mild skin irritation or redness.

Serious or Rare Side Effects

• Venous thromboembolism: blood clots in veins, potentially life‑threatening.
• Severe neutropenia: markedly low neutrophils requiring medical intervention.
• Severe thrombocytopenia: dangerously low platelets causing bleeding.
• Secondary primary malignancies: emergence of new cancers.
• Stevens‑Johnson syndrome: severe skin reaction with blistering.
• Hepatic failure: significant liver dysfunction.

Before initiating Lenalidomide therapy, several precautions should be observed to minimize risks.

• Monitor blood counts: perform regular complete blood count tests to detect cytopenias.
• Assess thromboembolic risk: evaluate patient history and consider prophylactic anticoagulation when indicated.
• Contraindicated in pregnancy: avoid use in pregnant women and ensure effective contraception.
• Adjust for renal impairment: dose may need modification in patients with reduced kidney function.
• Use contraception: both male and female patients should employ reliable birth control methods.
• Store at ambient temperature: keep tablets in the original packaging, protect from moisture and light.

Lenalidomide can interact with other medicines, influencing its efficacy or safety profile.

Major Interactions (Avoid)

• Strong CYP3A4 inducers (e.g., rifampin): markedly reduce lenalidomide exposure.
• Strong CYP3A4 inhibitors (e.g., ketoconazole): increase drug levels and toxicity risk.
• Anticoagulants (e.g., warfarin): heightened bleeding risk.
• Live vaccines: risk of infection due to immunosuppression.

Moderate Interactions (Monitor Closely)

• NSAIDs (e.g., ibuprofen): may increase bleeding tendency.
• Hormonal contraceptives: reduced effectiveness, consider alternative methods.
• CYP3A4 substrate drugs (e.g., midazolam): possible altered plasma concentrations.